JP2010016109A - Concentrating photovoltaic power generation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a concentrating photovoltaic power generation system wherein a light condensing method and a method of tracking daily variation and seasonal variation of sunbeam are devised to reduce the area for mounting a photovoltaic power generation cell, with a higher efficiency of power generation. <P>SOLUTION: A cylindrical lens 10 is so arranged that the beam which is the condensation of sunbeam received with a light receiving surface runs in almost east-west direction. A slit body 20 includes an almost linear slit 21, and is arranged below the cylindrical lens 10 so that the sunbeam condensed with the cylindrical lens 10 passes through the slit 21. A photovoltaic power generation cell array 30 is arranged below the slit body 20 so as to receive the sunbeam having passed through the slit 21 of he slit body 20. There are provided a relative position adjusting mechanism 40 for adjusting relative distance among the cylindrical lens 10, the slit body 20, and the photovoltaic power generation cell array 30 according to the incident angle resulting from daily fluctuation and seasonal variation of the sunbeam, and a north-south direction elevation angle adjusting mechanism 50 for adjusting elevation angle in north-south direction of them. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for increasing the power generation efficiency of a concentrating solar power generation apparatus that generates power by concentrating sunlight on a solar cell by a condensing lens.

  A conventional solar power generation system for ordinary houses is not a concentrating solar power generation system that condenses sunlight by a condensing means such as a condensing lens or a concave mirror, so it is used in one solar power generation cell. Sunlight is only equivalent to the light receiving area of the photovoltaic cell. Therefore, in order to increase the amount of power generation in the solar power generation system, a large number of expensive solar power generation cells have to be arranged, resulting in a high cost of the solar power generation system. In addition, since the amount of sunlight used in the solar power generation cell is smaller than that of the concentrating type, the power generation efficiency is low. In addition, in the conventional photovoltaic power generation system, in order to increase the power generation efficiency even a little, an antireflection film is provided on the surface of the photovoltaic cell, but an antireflection film is provided on the surface of the photovoltaic cell. This was also a factor in increasing costs.

  Therefore, in the prior art, many concentrating solar power generation systems that can increase the power generation efficiency while reducing the number of installed solar power generation cells have been proposed.

For example, a concentrating solar power generation system that collects light using a circular lens is known.
An outline of a conventional concentrating solar power generation system configuration is as follows. A condensing plate having a plurality of condensing lenses for condensing sunlight using a plurality of condensing lenses, and a predetermined back side of the condensing plate. And a plurality of photovoltaic cells fixed at intervals, and each condensing lens is a circular convex lens.

  For example, US Pat. No. 5,118,361 discloses a condensing lens array plate in which a large number of circular lenses are arranged in an array and a photovoltaic power generation cell arranged in the focal position of each circular lens in an array. A distributed photovoltaic cell array board is disclosed.

  Further, a lens using a Fresnel lens as a circular lens is also known. The technique described in Japanese Patent Application Laid-Open No. 2005-142373 collects light using a circular Fresnel lens and arranges a photovoltaic power generation cell at the focal position. Note that the object of the invention of Japanese Patent Laid-Open No. 2005-142373 is not to improve the efficiency of power generation, but to effectively use the scattered light generated on the stepped surface of the Fresnel lens. The invention aims to allow solar power generation and rooftop greening at the same time by passing a plant on the ground hidden behind the apparatus.

JP 2005-142373 A US Pat. No. 5,118,361

  However, the direction of arrival of sunlight changes from moment to moment due to daily fluctuations and seasonal fluctuations of the sun. In the concentrating solar power generation system that collects light using the circular lens in the above-mentioned conventional technology, sunlight is concentrated at one point. However, since the position where the focus is formed moves in the three-dimensional space, in order to arrange the photovoltaic cell at the focal position, the position of the photovoltaic cell array is aligned three-dimensionally, or a circular lens and sunlight A driving device that rotates the three axes so that the power generation cell array is integrated and faces the direction of arrival of the sun like a sunflower is required. Using this drive mechanism is complicated and expensive, and the drive mechanism increases the height of the concentrating solar power generation system. There was a drawback that sufficient strength was required for the installation structure such as the body and the roof, and the cost was high. Further, in a system in which sunlight is concentrated at one point, although depending on the area of the lens, the energy concentrated at the one point becomes very large, so there is a problem when the temperature rises and some kind of cooling structure is required. . If the lens is divided into small parts, the cooling can be omitted, but the structure is complicated.

In view of the above problems, the present invention devised a tracking method and a condensing method for daily fluctuations and seasonal fluctuations of solar rays in a solar power generation system, and reduces power generation efficiency while reducing the mounting area of expensive solar power generation cells. An object of the present invention is to provide a concentrating solar power generation system that does not require a special cooling mechanism.
It is another object of the present invention to provide a concentrating solar power generation system that suppresses the weight and height of the solar power generation system and can easily withstand storms.

In order to achieve the above object, a first concentrating solar power generation system of the present invention includes:
A cylindrical lens that focuses sunlight received by the light-receiving surface as a substantially linear light beam, the cylindrical lens arranged so that the focused light beam is in a substantially east-west direction, and
A photovoltaic cell array in which photovoltaic cells that generate sunlight and generate electric power are arranged, and the photovoltaic cell array arranged below the cylindrical lens so as to receive the light beam collected by the cylindrical lens; ,
A relative position adjustment mechanism for adjusting a relative distance between the cylindrical lens and the photovoltaic cell array according to an incident angle of sunlight;
In accordance with the incident angle of sunlight, the cylindrical lens and a north-south elevation angle adjusting mechanism that adjusts the north-south elevation angle of the photovoltaic cell array are provided.
With the above configuration, by providing a mechanism for adjusting the relative position of the cylindrical lens and the photovoltaic cell array and a mechanism for adjusting the elevation angle in the north-south direction, it is possible to cope with changes in the direction of arrival of sunlight accompanying the daily and seasonal variations of the sun. The angle of the device so that the sunlight can be focused at an appropriate elevation angle and received on the photovoltaic cell array at any time of morning, noon and evening, and any day of spring, summer, autumn and winter The amount of received sunlight increases, and it is possible to efficiently generate power with a smaller number of photovoltaic power generation cells.

Here, in the configuration of the first concentrating solar power generation system, as the first pattern for adjusting the relative distance between the cylindrical lens and the solar power generation cell array by the relative position adjustment mechanism, the solar power generation There is a pattern for moving the relative position of the cylindrical lens with respect to the cell array.
In other words, the focal length (the depth connecting the focal points) changes depending on the incident angle in the east-west direction as seen from the north-south direction of the sunlight, which changes with the daily fluctuation of the sun. The position for connecting the focal points (depth for connecting the focal points) is adjusted to the position (depth) of the photovoltaic cell array.

Further, in the configuration of the first concentrating solar power generation system, as a second pattern for adjusting the relative distance between the cylindrical lens and the solar power generation cell array by the relative position adjustment mechanism, the second lens is adjusted with respect to the cylindrical lens. Thus, there is a pattern for moving the relative position of the photovoltaic cell array.
In other words, the focal length (the depth connecting the focal points) changes depending on the incident angle in the east-west direction as seen from the north-south direction of the sunlight that changes with the daily fluctuation of the sun, but the photovoltaic cell array below is moved up and down Thus, the position where the sunlight focuses (the depth at which the focus is focused) is adjusted to the position (depth) of the photovoltaic cell array.

Next, as the second concentrating solar power generation system of the present invention, in addition to the configuration of the first concentrating solar power generation system,
A substantially linear slit, and at least a part of the rear surface is a slit body that is a reflector, and is positioned between the cylindrical lens and the photovoltaic cell array, and is substantially linearly focused by the cylindrical lens. Including a slit body disposed below the cylindrical lens so that the light passes through the slit and the light passing through the slit is received by the photovoltaic cell array,
Of the sunlight that has entered the photovoltaic cell array through the slit of the slit body, the sunlight reflected by the surface of the photovoltaic cell array is reflected by the reflector on the back surface of the slit body. Re-entering the photovoltaic cell array and repeating the reflection and re-incidence between the back surface of the slit body and the photovoltaic cell array to increase the amount of light provided for power generation in the photovoltaic cell array. And

  Here, as a first pattern for adjusting a relative distance between the cylindrical lens, the slit body, and the photovoltaic cell array by a relative position adjusting mechanism, the cylindrical lens is arranged with respect to the slit body and the photovoltaic cell array. There is a pattern to move the relative position of. In other words, the focal length (the depth connecting the focal points) changes depending on the incident angle in the east-west direction as seen from the north-south direction of the sunlight, which changes with the daily fluctuation of the sun. The position for connecting the focal points (depth for connecting the focal points) is adjusted to the position (depth) of the photovoltaic cell array.

Next, as a second pattern for adjusting a relative distance between the cylindrical lens, the slit body, and the photovoltaic cell array by a relative position adjusting mechanism, the slit body and the photovoltaic cell array are arranged with respect to the cylindrical lens. There is a pattern to move the relative position of.
In other words, the focal length (the depth connecting the focal points) changes depending on the incident angle in the east-west direction seen from the north-south direction of the sunlight that changes with the daily fluctuation of the sun, but the slit body and photovoltaic cell array below , The position where the sunlight focuses (the depth at which the focus is focused) is adjusted to the position (depth) of the photovoltaic cell array.

  Next, as a third pattern for adjusting a relative distance between the cylindrical lens, the slit body, and the photovoltaic cell array by a relative position adjustment mechanism, the slit body is arranged with respect to the cylindrical lens and the photovoltaic cell array. There is a pattern to move the relative position of. In other words, the focal length (the depth connecting the focal points) changes depending on the incident angle in the east-west direction seen from the north-south direction of sunlight that changes with the daily fluctuation of the sun, but by raising and lowering only the slit body below, The position where the sunlight focuses (the depth at which the focus is focused) is adjusted to the position (depth) of the slit, so that the sunlight passes through the slit and guides the light into the cavity where the photovoltaic power generation cell is located. It will generate electricity.

  Thus, by providing a mechanism for adjusting the relative position of the cylindrical lens, slit body, photovoltaic cell array, and a mechanism for adjusting the elevation angle in the north-south direction, the arrival direction of sunlight accompanying the daily and seasonal variations of the sun So that sunlight can be focused at an appropriate elevation angle and received on the photovoltaic cell array at any time of morning, afternoon, and evening, and any day of spring, summer, autumn or winter. The angle of the device can be adjusted, the amount of received sunlight is increased, and it is possible to efficiently generate power with a smaller number of photovoltaic power generation cells.

In addition, it is preferable that the said photovoltaic power generation cell shall be a transmissive | pervious cell, and let the sunlight which is not consumed by electric power generation pass.
By using a transmissive cell, light that is not used for photoelectric conversion passes through the photovoltaic cell, repeatedly reflects on the inner wall of the cavity, and can enter the photovoltaic cell again. That is, it is possible to improve the photoelectric conversion efficiency in the solar power generation cell of the sunlight guided into the cavity.

  When this transmission type cell is adopted, it is effective to provide a cavity provided with a reflector on the inner wall surface and surround the photovoltaic cell array with the reflector. That is, the slit body includes a cavity that is provided below the slit body and surrounds the photovoltaic cell array, and is provided with a reflector that reflects light on at least a partial region of the inner wall surface thereof. Of the sunlight that has passed through the slit and entered the cavity, sunlight that has passed through the transmission cell without being converted into power generation energy is reflected between the reflector on the inner wall surface of the cavity and the back surface of the slit body. The light is repeatedly reflected between the reflectors to increase the amount of light provided for power generation in the photovoltaic cell array.

In addition, the photovoltaic cell array includes at least two photovoltaic power generation cells in which the wavelength band with high power generation efficiency is the first wavelength band, and two photovoltaic power generation cells in which the wavelength band with high power generation efficiency is the second wavelength band. It is also preferable to include types of cells.
By combining solar power generation cells having different wavelength bands suitable for photoelectric conversion, the power generation utilization efficiency of solar light is improved. For example, if a combination of light having a long wavelength (light from infrared rays) with high power generation efficiency and light having a short wavelength (light from ultraviolet rays) having high power generation efficiency, a versatile wavelength band introduced into the cavity Can be effectively photoelectrically converted.

Next, the device of the slit will be described.
The slit only needs to have a width that allows a linear light beam connected by the cylindrical lens to pass therethrough, and serves as a lid on the upper surface of the cavity. In order to improve the sealing performance of the cavity, it is preferable that the slit width is narrow. However, in some weather conditions, the slit width is narrow, but the introduction of light into the cavity may not be successful. For example, when the sunlight is incident not only as straight light but also as scattered light as in cloudy weather, it is difficult to focus, so it is better to widen the slit to keep the opening area of the system housing large. Therefore, it is preferable that the slit body includes a slit width adjusting mechanism that increases or decreases the slit width.

The slit width adjusting means of the slit width adjusting mechanism is not limited. For example, the slit body is composed of two plate-like members that face each other independently, and the slit width is increased or decreased by sliding the slit body. There is something.
Further, the slit body is composed of two plate-like members facing each other independently, the slit is formed between the opposing edges of the plate-like member, and the slit width adjusting mechanism is provided in the plate-like member. There is one that increases or decreases the width of the slit by rotating the plate-like member around the rotation axis.

Next, a configuration in which the cylindrical lens is a Fresnel lens is also preferable.
With the above structure, the weight of the lens can be suppressed, so that the material cost can be reduced and the thickness can be reduced, which is advantageous in securing the mechanical structure strength. In addition, since the thickness of the lens can be suppressed, the height of the housing can be reduced, and the structure can easily withstand storms.

Moreover, it is preferable to perform photocatalyst coating processing on the outer surface of the cylindrical lens on the sunlight receiving surface side.
The above configuration makes it difficult for dirt to adhere to the outer surface of the cylindrical lens even if it is installed under conditions exposed to the outside environment such as the rooftop, so that a large amount of received sunlight can be secured and cleaning work can be reduced. You can also

According to the concentrating solar power generation system of the present invention, the solar ray tracking method and the concentrating method in the solar power generation system have been devised to increase the power generation efficiency while reducing the mounting area of expensive solar power generation cells. Can be.
According to the concentrating solar power generation system of the present invention, the height of the system housing can be kept low and it can easily withstand storms.

  Hereinafter, embodiments of the concentrating solar power generation system of the present invention will be described with reference to the drawings. However, it goes without saying that the scope of the present invention is not limited to the specific application, shape, number, etc. shown in the following examples.

The example of the concentrating solar power generation system of this invention concerning Example 1 is shown.
1 and 2 are diagrams showing a configuration example of a first concentrating solar power generation system according to the present invention.
FIG. 1 is a diagram schematically showing a plan view, a front view, and a side view of a concentrating solar power generation system 100.
FIG. 2 is a diagram schematically showing a transverse sectional view and a longitudinal sectional view of the concentrating solar power generation system 100.
FIG. 3 is a diagram schematically showing, in a vertical cross section in the side surface direction, the received sunlight is collected by the cylindrical lens 10, passes through the slit body 20 and is received by the photovoltaic power generation cell array 30.

  In the configuration example of the first embodiment, the concentrating solar power generation system 100 includes a cylindrical lens 10, a slit body 20, a solar power generation cell array 30, a relative position adjustment mechanism 40, a north-south direction elevation angle adjustment mechanism 50, a cavity 60, a housing. A body 70 is provided.

The cylindrical lens 10 is made of a transparent material such as glass or plastic resin, and focuses sunlight received by the light receiving surface as a substantially linear light beam, and is a plano-convex lens. In this configuration, the cylindrical lens 10 is a Fresnel lens. By using a Fresnel lens, it is less bulky than a cylindrical lens, it is lightweight, material costs can be reduced, and the overall height of the device can be reduced, and the concentrated sun is exposed to the external environment such as wind and rain. This is because it is advantageous for the photovoltaic system 100. Even in the case of a Fresnel lens, the light collecting effect is basically the same as that of a hemispherical plano-convex lens.
In this apparatus configuration example, the cylindrical lens 10 has a plano-convex lens whose upper surface is a flat surface and whose lower surface is a convex surface. The plane of the upper surface serves as a sunlight receiving surface, is refracted at the boundary surface that exits the cylindrical lens 10, and is condensed into a substantially linear light beam at a position away from the focal length.
Moreover, it is preferable to apply a photocatalytic coating to the outer surface of the cylindrical lens 10 on the sunlight receiving surface side. If the photocatalyst coating is applied, dirt is less likely to adhere to the outer surface of the cylindrical lens 10 even if the entire apparatus is installed under conditions that are exposed to the outside environment such as the rooftop, so that a large amount of received light from the sun is secured. In addition, the cleaning work can be reduced. The photocatalyst coating agent is not particularly limited, and examples thereof include a titanium oxide coating agent.

  Here, the cylindrical lens 10 is arranged so that the converged light beam is in the east-west direction. That is, if it arrange | positions so that the axis | shaft of a cylinder may become an east-west direction, the focused light beam will become an east-west direction. If the converged light rays are arranged in the east-west direction, the light rays converged in most of the daily movement of the sun rising from the east and sinking to the west become linear rays extending in the east-west direction at the focal length, and the efficiency This is because it can capture sunlight.

  Next, the slit body 20 is provided with a substantially linear slit 21 and is disposed below the cylindrical lens so that the substantially linear light beam converged by the cylindrical lens passes through the slit 21. The shape of parts other than the slit 21 is not ask | required. For example, two pieces of plate-like bodies may face each other and the gap between them may be the slit 21. The arrangement direction of the slits 21 is the east-west direction. At least a part of the back surface of the slit body 20 is a reflector 22. In this example, the entire back surface is the reflector 22. Further, at least a part of the inner wall surface of the housing 70 is a reflector 71. In this example, the entire inner wall surface is a reflector 71.

  The photovoltaic power generation cell array 30 is an array of photovoltaic power generation cells that generate power by receiving sunlight. It arrange | positions under the plate-shaped body so that the light beam which passed the slit 21 of the slit body may be received. For example, it can be set as the arrangement | sequence which has arrange | positioned the photovoltaic cell to the rectangular area | region long in the east-west and short in the north-south. As shown in FIGS. 1 and 2, the arrangement of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 in the south-northeast-west direction is arranged with the east-west direction as an axis.

  FIG. 3 shows a state in which the received sunlight is collected by the cylindrical lens 10, passes through the slit body 20, and is received by the photovoltaic power generation cell array 30 from a longitudinal section in the side surface direction. The elevation angle in the north-south direction shown in FIG. 3 is an example.

  Here, in consideration of the cost of the photovoltaic cell and the performance of the power generation efficiency, the rectangular region of the photovoltaic cell array 30 is configured to be as small as possible (the number of photovoltaic cells is small), and the entire rectangular region is cylindrical. It is preferable that the light beam that has been focused by the lens 10 and passed through the slit 21 is projected. As described above, the conditions for minimizing the rectangular area in which the photovoltaic cells are arranged will be described.

  In the present invention, the plano-convex cylindrical lens 10 is employed to reduce the projected area of the light beam by refracting the sunlight received on the plane side at the boundary surface of the convex surface and focusing it linearly. The projected area of the light beam at the position of the photovoltaic cell array 30 varies depending on the light arrival direction, the relative distance in the vertical direction of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30. Since the direction of arrival of the sun varies from east to west due to daily fluctuations, the focal length (depth) changes from moment to moment when the installation state of the concentrating solar power generation system 100 is fixed against daily fluctuations. It will be. The present invention focuses on this point, and includes a relative position adjustment mechanism 40 that adjusts the relative distance between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 according to the focal length determined by the incident angle of sunlight. It is said.

  There are a plurality of patterns for adjusting the relative distance between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 by the relative position adjusting mechanism 40. Each pattern is described below.

In the first pattern, the relative position adjusting mechanism 40 moves the cylindrical lens 10 without moving the slit body 20 and the photovoltaic power generation cell array 30 to move the relative positions of the two.
4 and 5 are diagrams schematically showing how the relative distances between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 are adjusted by the relative position adjusting mechanism 40 that is driven by the first pattern. The detailed illustration of the mechanical structure of the relative position adjusting mechanism 40 is omitted, and is only schematically shown. The drive mechanism itself of the relative position adjusting mechanism 40 is not particularly limited as long as it moves the casing that supports the cylindrical lens 10 with respect to the slit body 20 and the photovoltaic cell array 30, and includes a motor, a wheel, a wire, The mechanical mechanism of driving such as a piston is not limited.

  As shown in FIGS. 4 (a) and 4 (b), if the sun rays are coming from a low east angle (for example, an elevation angle of 30 degrees with respect to the ground) in the morning, the light passes through the cylindrical lens 10 and is focused. If the focal length (the depth at which the focal point is) is relatively shallow and the focal point is formed at the distance (depth) shown in FIGS. 4A and 4B, the cylindrical lens 10 is moved by the relative position adjustment mechanism 40. The relative movement is made so that the focal point is formed at the depth at which the slit body 20 and the photovoltaic cell array 30 exist, and the solar radiation is received in the rectangular region where the photovoltaic cell array 30 is arranged. .

  Next, as shown in FIGS. 5 (a) and 5 (b), assuming that the sunbeams arrive at a high south angle (for example, an elevation angle of 70 degrees with respect to the ground) at noon, they pass through the cylindrical lens 10. If the focal length (depth at which the focal point is focused) becomes relatively deeper than in the morning and the focal point is formed at the position (depth) in FIGS. 5A and 5B, the relative position adjusting mechanism 40 The cylindrical lens 10 is moved relative to each other, and adjusted so that the focal point is formed at the depth at which the slit body 20 and the photovoltaic cell array 30 exist, so that the sunlight is received in the rectangular region where the photovoltaic cell array 30 is disposed. It has become.

By mounting the relative position adjusting mechanism 40 driven by the first pattern and adjusting the relative distances between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30, it is possible to reduce the number of photovoltaic cells. It is possible to use sunlight for the area of the plane side of the cylindrical lens 10 for power generation in any number of solar power generation cell arrays 30 of the number mounted.
In addition, after entering into the cavity 60, a device for improving the photoelectric conversion efficiency in the photovoltaic cell array 30 by reflection by the reflector 22 provided on the back surface of the slit body 20 and the reflector 71 provided on the inner wall surface of the cavity 60. Will be described later.

  Next, the second pattern is the adjustment of the relative distance between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30. The relative position adjustment mechanism 40 controls the slit body 20 and the photovoltaic cell array with respect to the cylindrical lens 10. 30 relative positions are moved. That is, without moving the cylindrical 10, the slit body 20 and the photovoltaic power generation cell array 30 are moved to move the relative positions of the two.

  6A and 6B schematically show how the relative distances between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 are adjusted by the relative position adjusting mechanism 40 that is driven in the second pattern. FIG. As in FIG. 4, the detailed structure of the mechanical structure of the relative position adjusting mechanism 40 is not shown.

  As shown in FIGS. 6 (a) and 6 (b), if the sun rays are coming from a low east angle (for example, an elevation angle of 30 degrees with respect to the ground) in the morning, the light passes through the cylindrical lens 10 and converges. If the focal length (the depth at which the focal point is focused) is relatively shallow and the focal point is formed at the positions shown in FIGS. 6 (a) and 6 (b), a cylindrical shape is obtained as shown in FIGS. 6 (a) and 6 (b). The lens 10 moves relatively so that the focal length of the light beam (the depth at which the focal point is focused) is located at the position of the slit body 20 and the photovoltaic cell array 30, and the sunlight rays are emitted in the rectangular region where the photovoltaic cell array 30 is arranged. To receive.

  Next, as shown in FIGS. 7 (a) and 7 (b), assuming that the sunbeams arrive at a high south angle (for example, an elevation angle of 70 degrees with respect to the ground) at midday, the light passes through the cylindrical lens 10. Assuming that the focal length (the depth at which the focal point is focused) is relatively deeper than in the morning, and the focal point is formed at the position shown in FIGS. 7A and 7B, FIGS. 7A and 7B. The rectangular lens 10 is moved relative to the cylindrical lens 10 so that the focal length of the light beam (the depth at which the focal point is focused) is positioned between the slit body 20 and the photovoltaic cell array 30, and the photovoltaic cell array 30 is disposed. It is designed to receive sunlight in the area.

By mounting the relative position adjusting mechanism 40 driven by the second pattern and adjusting the relative distances between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30, it is possible to reduce the number of photovoltaic cells. It is possible to use sunlight for the area of the plane side of the cylindrical lens 10 for power generation in any number of solar power generation cell arrays 30 of the number mounted.
In addition, after entering into the cavity 60, a device for improving the photoelectric conversion efficiency in the photovoltaic cell array 30 by reflection by the reflector 22 provided on the back surface of the slit body 20 and the reflector 71 provided on the inner wall surface of the cavity 60. Will be described later.

  Next, as a third pattern, the relative position of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 is adjusted by the relative position adjustment mechanism 40 with respect to the cylindrical lens 10 and the photovoltaic cell array 30. The relative position of 20 is moved. That is, without moving the cylindrical 10 and the photovoltaic power generation cell array 30, the slit body 20 is moved to move the relative position between them.

  FIGS. 8A and 8B schematically show how the relative distance adjustment mechanism 40 driven by the third pattern adjusts the relative distances between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30. FIG. As in FIG. 4, the details of the mechanical structure of the relative position adjusting mechanism 40 are not shown.

  As shown in FIGS. 8 (a) and 8 (b), if the sun rays arrive in the morning from an eastern low angle (for example, an elevation angle of 30 degrees with respect to the ground), they pass through the cylindrical lens 10 and converge. Assuming that the focal length (the depth at which the focal point is focused) is relatively shallow and the focal point is formed at the position shown in FIGS. 8A and 8B, the slits as shown in FIGS. 8A and 8B. The body 20 moves relative to the focal length of the light beam (the focal depth), the linear light beam focused by the cylindrical body 10 passes through the slit body 20, and the lower photovoltaic cell array 30 is arranged. It directs sunlight into the cavity. As will be described later in Example 2, the solar light guided into the cavity is light that is not used for power generation in the photovoltaic cell if the back surface of the slit body 20 and the inner wall of the cavity 60 are mirror-finished. Will repeat reflection until it enters the photovoltaic cell.

  Next, as shown in FIGS. 9 (a) and 9 (b), assuming that the sunbeams arrived from a high south angle (for example, an elevation angle of 70 degrees with respect to the earth) at noon, they passed through the cylindrical lens 10. Assuming that the focal length (the depth at which the focal point is focused) is relatively deeper than in the morning and the focal point is formed at the positions shown in FIGS. 9A and 9B, the slit body 20 has a focal length (focal point) of the light beam. The linear light beam that is relatively moved so as to be located at a certain depth) passes through the slit body 20 through the cylindrical body 10, and the solar light is directed into the cavity in which the photovoltaic cell array 30 below is disposed. It is a guide.

The relative position adjusting mechanism 40 driven by the third pattern is mounted and the relative distances between the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 are adjusted to guide all the sunlight into the cavity 60. In any time zone, the solar power generation cell array 30 in the cavity 60 can use sunlight for power generation.
In addition, after entering into the cavity 60, a device for improving the photoelectric conversion efficiency in the photovoltaic cell array 30 by reflection by the reflector 22 provided on the back surface of the slit body 20 and the reflector 71 provided on the inner wall surface of the cavity 60. Will be described later.

Next, the device for adjusting the elevation angle in the north-south direction will be described.
In the concentrating solar power generation system of the present invention, the north-south direction elevation angle adjustment is performed in which the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 are integrated to adjust the north-south elevation angle according to the incident angle of sunlight. A configuration including the mechanism 50 is preferable.
The trajectory of the sun varies from day to day depending on the season, and the direction of arrival of sunlight is high at midday in the north-south direction during summer and low in the north-south direction in winter.

As the sun changes daily, the incident angle (elevation angle) in the north-south direction seen from the east-west direction and the incidence angle in the east-west direction (elevation angle) seen from the north-south direction change from moment to moment. Go. Among the daily fluctuations of the sun, for the fluctuation of the elevation angle in the east-west direction, the cylindrical lens 10 is used to converge the light beam on the east-west line, and the relative position adjustment mechanism 40 causes the cylindrical lens 10 and the slit pair to converge. Adjustment is made by adjusting the relative distance between the solar cell array 30 and the solar cell array 30, and the north-south elevation angle adjusting mechanism 50 adjusts the north-south elevation angle variation among the daily variations of the sun. The elevation angle in the north-south direction at the same time changes due to the seasonal variation of the sun. Needless to say, the north-south elevation angle adjustment mechanism 50 can cope with the seasonal variation every day. For example, it is well known that the elevation angle in the north-south direction at noon differs 47 degrees (twice the inclination of the earth axis) between the winter solstice and the summer solstice.
In other words, according to the present invention, the cylindrical lens 10, the slit body 20, and the sunlight are adjusted by the relative position adjustment mechanism 40 while the north-south elevation angle adjustment mechanism 50 adjusts the elevation angle in the north-south direction every moment in accordance with the daily fluctuation of the sun. The relative position of the power generation cell array 30 is adjusted every moment so that the sunlight is focused on the photovoltaic cell array 30 in a substantially straight line in any time zone in any season.

  FIG. 10 is a diagram schematically showing how the north-south direction elevation angle adjustment mechanism 50 adjusts the elevation angle in the north-south direction by integrating the cylindrical lens 10, the slit body 20, and the photovoltaic power generation cell array 30. The mechanical structure of the north-south elevation angle adjusting mechanism 50 is not shown. The drive mechanism itself of the north-south direction elevation angle adjusting mechanism 50 is not particularly limited, and for example, as long as the entire housing 70 in which the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 are mounted is moved relative to the ground. Well, the mechanical mechanism of driving, such as a motor, a wheel, a wire, and a piston, is not limited.

  As shown in FIG. 10A, assuming that the sunbeams are coming from a low angle (for example, an elevation angle of 40 degrees with respect to the ground) at midday in winter, the elevation angle in the north-south direction of the entire housing 70 is adjusted by the north-south elevation angle adjustment mechanism 50. Is adjusted so as to be the angle (elevation angle of 40 degrees with respect to the ground) and adjusted so that the sunlight comes from the direction facing the concentrating photovoltaic power generation system 100 (90 degrees). Sunlight is received in a rectangular area where the cell array 30 is arranged.

  Next, as shown in FIG. 10B, assuming that the sunbeams are coming from a high angle (for example, an elevation angle of 70 degrees with respect to the ground) at midday in the summer, the north-south direction elevation angle adjustment mechanism 50 causes the north-south of the entire housing 70 to be Adjust the elevation angle of the direction to be the angle (elevation angle 70 degrees with respect to the ground), and adjust so that sunlight comes from the direction facing the concentrating solar power generation system 100 (90 degrees), Sunlight is received in a rectangular region where the photovoltaic cell array 30 is arranged.

  By mounting the above-described north-south direction elevation angle adjustment mechanism 50 and adjusting the elevation angle in the north-south direction of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30, a smaller number of solar cells can be mounted. In any time zone or any season in the photovoltaic cell array 30, it is possible to effectively use sunlight for the area on the plane side of the cylindrical lens 10 for power generation.

Next, after sunlight enters the cavity 60, the photoelectric conversion efficiency in the photovoltaic cell array 30 is increased by reflection by the reflector 22 provided on the back surface of the slit body 20 and the reflector 71 provided on the inner wall surface of the cavity 60. Describe how to improve.
In the concentrating solar power generation system 100 according to the first embodiment, a housing 70 that surrounds the side surface and the bottom surface of the photovoltaic cell array 30 is provided, and solar power generation is performed by the housing 70 and the slit body 20 that serves as a lid on the top surface. A cavity 60 that surrounds the cell array 30 is formed, and a reflector 22 that reflects light on the back surface of the slit body 20 and a reflector 71 that reflects light also on the inner wall surface of the housing 70 are provided. The amount of light provided for power generation in the photovoltaic cell array 30 is increased by the sunlight that passes through the slit 21 of the slit body 20 and enters the cavity 60 being repeatedly reflected by the reflector 22 and the reflector 71. is there.

As shown in FIG. 3, FIG. 4 (b), FIG. 5 (b), FIG. 6 (b), FIG. 7 (b), FIG. 8 (b), FIG. After the light is collected by the cylindrical lens 10, passes through the slit body 20 and enters the cavity 60, the sunlight repeatedly reflects on the reflector 22 and the reflector 71 and is received by the photovoltaic cell array 30.
As shown in the drawings, sunlight passes through the slit 21 of the slit body 20 and enters the cavity 60. Since the rear surface of the slit body 20 is provided with a mirror-like reflector 22 and the inner wall surface of the housing 70 is provided with a mirror-like reflector 71, sunlight that has once entered the cavity 60 is reflected unless it is absorbed. repeat. Here, since the element that absorbs sunlight in the cavity 60 is only each photovoltaic cell 31 of the photovoltaic cell array 30, the reflection is repeated until it enters the photovoltaic cell and is effectively used for photoelectric conversion. .

Here, various ideas about the photovoltaic power generation cell array 30 will be described.
The first device is a device in which the photovoltaic cell array 30 is a transmissive cell. The aim is to effectively use sunlight that is not consumed for power generation even if it is incident on the vicinity of a rectangular area of the photovoltaic cell array 30. If a mechanical structure that is not directly related to photoelectric conversion, such as a frame substrate, is an opaque material that absorbs light among the structures that constitute the photovoltaic cell array 30, light is attenuated in the rectangular region of the photovoltaic cell array 30. End up. Therefore, if the photovoltaic cell array 30 is a transmissive cell so that light that is not used for photoelectric conversion can be transmitted, the photovoltaic power generation efficiency is improved.

The second device is a photovoltaic cell array 30, solar power generation cells 31a in which at least the wavelength band with high power generation efficiency is the first wavelength band, and sunlight in which the wavelength band with high power generation efficiency is the second wavelength band. This is a device that includes two or more types of power generation cells 31b.
By combining solar power generation cells having different wavelength bands suitable for photoelectric conversion, the power generation utilization efficiency of solar light is improved. Although sunlight includes light of various wavelength bands as natural light, the photovoltaic power generation cell has a wavelength band of light that can efficiently perform photoelectric conversion according to its characteristics.

  FIG. 11 schematically shows the wavelength band of light received in the photovoltaic power generation cell and the photoelectric conversion efficiency. FIG. 11 schematically shows two photovoltaic power generation cells having different wavelength bands suitable for photoelectric conversion. For example, a solar power generation cell 31a having high power generation efficiency in light having a long wavelength (light from infrared rays) and a solar power generation cell 31b having high power generation efficiency in light having a short wavelength (light from ultraviolet rays) are illustrated. By combining the solar power generation cell 31a and the solar power generation cell 31b, it is possible to effectively photoelectrically convert light in various wavelength bands introduced into the cavity.

As described above, according to the concentrating solar power generation system of Example 1, the relative position of the cylindrical lens 10, the slit body 20, and the solar power generation cell array 30 is adjusted by mounting the relative position adjustment mechanism 40. High-efficiency solar power generation can be performed regardless of the daily fluctuations of the sun, and the north-south elevation angle adjustment mechanism 50 is installed to adjust the north-south elevation angle of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30. By doing so, high-efficiency solar power generation can be performed regardless of the seasonal variation of the sun.
Further, according to the concentrating solar power generation system of the first embodiment, the sunlight that has passed through the slit 21 is used in the solar cell 31 in the cavity 60 for photoelectric conversion, and the reflector 22 and the reflector 71. Therefore, a lot of sunlight is effectively photoelectrically converted in the photovoltaic cell and used for power generation. In addition, power generation is achieved by making the photovoltaic cell array a transmissive type or by combining multiple types of different wavelength bands with high photoelectric conversion efficiency as photovoltaic cells included in the photovoltaic cell array. Efficiency can be improved.

The concentrating solar power generation system 100a according to the second embodiment is a configuration example including a slit width adjusting mechanism 80 that increases or decreases the slit width of the slit body.
The slit body 20 has a role to cover the sun so that the sun that has once passed through the slit body 20 does not come out of the cavity 60 while securing the width through which the incoming sunlight passes. Although the focal length (depth) varies depending on the arrival direction of sunlight with respect to the cylindrical lens 10, in the configuration example of the first embodiment, the relative position adjustment mechanism 40 causes the relative position of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30. Was adjusted so that the slit body 20 was positioned near the focal length (depth) of sunlight, the slit width of the slit body 20 was kept small, and the role as a lid was emphasized.

  However, in the second embodiment, instead of changing the relative distance of the slit body 20 to the cylindrical lens, the width of the slit 21 of the slit body 20 is expanded and contracted by the slit width adjusting mechanism 80, so that the arrival direction of sunlight, the weather, etc. It corresponds to the situation of.

  In the configuration example of the first slit width adjusting mechanism 80a, the slit body 20 includes two plate-like members 23a and 23b that are independent from each other, and the slit 21 is formed between the opposing edges of the plate-like members 23a and 23b. In the state, the slit width is increased or decreased by sliding the plate-like members 23a and 23b. The drive mechanism itself of the slit width adjusting mechanism 80a is not particularly limited as long as the slit plate-like member of the slit body 20 is slid and moved, and the mechanical mechanism of driving such as a motor, a wheel, a wire, a piston, etc. is not limited. .

FIG. 12 is a diagram showing how the slit width is adjusted by the slit width adjusting mechanism 80a of the first configuration example. The slit width adjusting mechanism 80a is not shown.
As shown in FIG. 12, the relative position of the slit body 20 with respect to the cylindrical lens 10 or the like does not change, but the slit width increases or decreases.

In the configuration example of the second slit width adjusting mechanism 80b, the slit body 20 is composed of two plate-like members 23a and 23b independent from each other, and the slit 21 is formed between the opposing edges of the plate-like members 23a and 23b. In the state, the width of the slit 21 is increased or decreased by providing a mechanism for rotating the plate member about the rotation axis provided on the plate member. FIG. 13 is a diagram showing how the slit width is adjusted by the slit width adjusting mechanism 80b of the second configuration example. The slit width adjusting mechanism 80b is not shown.
As shown in FIG. 13, the plate-like members 23a and 23b are provided with a rotation shaft, and can rotate around the rotation shaft.
As shown in FIG. 13 (a), when the rotation angle is increased, the interval between the opposing edges of the plate-like members 23a and 23b is increased, and when the rotation angle is reduced as shown in FIG. The interval between facing edges is reduced.

  Next, the use of the slit width adjusting mechanisms 80a and 80b depending on the weather will be described. For example, when the sunlight is not only straight light but also scattered light from the outside, such as cloudy sky, it is difficult to focus and there is no portion where solar energy is concentrated. In this situation, if the slit width is kept small, the amount of light entering the cavity 60 cannot be sufficiently secured. Therefore, on a cloudy day or the like, it is better to widen the slit 21 to keep the cavity opening area large. Therefore, the slits are enlarged by the slit width adjusting mechanisms 80a and 80b.

  According to the concentrating photovoltaic power generation system 100a according to the second embodiment, the width of the slit 21 of the slit body 20 can be adjusted by the slit width adjusting mechanism 80, and flexibly responds to the situation such as the direction of arrival of sunlight and the weather. can do.

  While preferred embodiments of the invention have been illustrated and described, it will be appreciated that various changes can be made without departing from the scope of the invention.

The figure which showed the top view of the concentrating photovoltaic power generation system 100, the front view, and the side view typically The figure which showed typically the cross-sectional view and longitudinal cross-sectional view of the concentrating solar power generation system 100 The figure which showed typically a mode that the sunlight received by the photovoltaic cell array 30 in the longitudinal cross-section in a side surface direction The figure which shows a mode that the relative distance of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 is adjusted with the relative position adjustment mechanism 40 driven with a 1st pattern (the 1). The figure which shows a mode that the relative position adjustment mechanism 40 driven with a 1st pattern adjusts the relative distance of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 (the 2). The figure which shows a mode that the relative distance of the cylindrical lens 10, the slit body 20, and the photovoltaic power generation cell array 30 is adjusted with the relative position adjustment mechanism 40 driven with a 2nd pattern (the 1). The figure which shows a mode that the relative distance of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 is adjusted with the relative position adjustment mechanism 40 driven with a 2nd pattern (the 2). The figure which shows a mode that the relative distance of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 is adjusted with the relative position adjustment mechanism 40 driven with a 3rd pattern (the 1) The figure which shows a mode that the relative distance of the cylindrical lens 10, the slit body 20, and the photovoltaic cell array 30 is adjusted with the relative position adjustment mechanism 40 driven with a 3rd pattern (the 2). The figure which shows a mode that the north-south direction elevation angle adjustment mechanism 50 adjusts the elevation angle of the north-south direction integrally with the cylindrical lens 10, the slit body 20, and the photovoltaic power generation cell array 30. FIG. The figure which shows typically the wavelength range and photoelectric conversion efficiency of the light which is received in the photovoltaic cell The figure which shows the mode of adjustment of the slit width by the slit width adjustment mechanism 80a of a 1st structural example. The figure which showed the mode of adjustment of the slit width by the slit width adjustment mechanism 80b of a 2nd structural example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cylindrical lens 20 Slit body 21 Slit 22 Reflector 23a, 23b Plate-shaped member 30 Photovoltaic cell array 40 Relative position adjustment mechanism 50 Cavity 60 North-south direction elevation angle adjustment mechanism 70 Case 71 Reflector 80a, 80b Slit width adjustment mechanism 100, 100a Concentrating solar power generation system

Claims (15)

A cylindrical lens that focuses sunlight received by the light-receiving surface as a substantially linear light beam, the cylindrical lens arranged so that the focused light beam is in a substantially east-west direction, and
A photovoltaic cell array in which photovoltaic cells that generate sunlight and generate electric power are arranged, and the photovoltaic cell array arranged below the cylindrical lens so as to receive the light beam collected by the cylindrical lens; ,
A relative position adjustment mechanism for adjusting a relative distance between the cylindrical lens and the photovoltaic cell array according to an incident angle of sunlight;
A concentrating solar power generation system comprising the cylindrical lens and a north-south elevation angle adjusting mechanism for adjusting a north-south elevation angle of the photovoltaic cell array in accordance with an incident angle of the sunlight.   The adjustment of the relative distance between the cylindrical lens and the photovoltaic cell array by the relative position adjustment mechanism moves the relative position of the cylindrical lens with respect to the photovoltaic cell array. Concentrated solar power generation system.   The adjustment of the relative distance between the cylindrical lens and the photovoltaic cell array by the relative position adjusting mechanism moves the relative position of the photovoltaic cell array with respect to the cylindrical lens. Concentrated solar power generation system. A substantially linear slit, and at least a part of the rear surface is a slit body that is a reflector, and is positioned between the cylindrical lens and the photovoltaic cell array, and is substantially linearly focused by the cylindrical lens. Including a slit body disposed below the cylindrical lens so that the light passes through the slit and the light passing through the slit is received by the photovoltaic cell array,
Of the sunlight that has entered the photovoltaic cell array through the slit of the slit body, the sunlight reflected by the surface of the photovoltaic cell array is reflected by the reflector on the back surface of the slit body. Re-entering the photovoltaic cell array and repeating the reflection and re-incidence between the back surface of the slit body and the photovoltaic cell array to increase the amount of light provided for power generation in the photovoltaic cell array. The concentrating solar power generation system according to claim 1.   Adjustment of the relative distance between the cylindrical lens, the slit body, and the photovoltaic cell array by the relative position adjustment mechanism moves the relative position of the cylindrical lens with respect to the slit body and the photovoltaic cell array. The concentrating solar power generation system according to claim 4.   Adjustment of the relative distance between the cylindrical lens, the slit body, and the photovoltaic cell array by the relative position adjustment mechanism moves the relative position of the slit body and the photovoltaic cell array with respect to the cylindrical lens. The concentrating solar power generation system according to claim 4.   Adjustment of the relative distance between the cylindrical lens, the slit body, and the photovoltaic cell array by the relative position adjustment mechanism moves the relative position of the slit body with respect to the cylindrical lens and the photovoltaic cell array. The concentrating solar power generation system according to claim 4.   The concentrating solar according to any one of claims 1 to 7, wherein the solar power generation cell is a transmissive cell, and sunlight that has not been converted into power generation energy by the solar power generation cell is allowed to pass through. Photovoltaic system. A cavity that is provided below the slit body and surrounds the photovoltaic cell array, and includes a cavity provided with a reflector that reflects light on at least a part of the inner wall surface thereof,
Of the sunlight that has passed through the slit of the slit body and entered the cavity, the sunlight that has passed through the transmissive cell without being converted into power generation energy is reflected on the reflector on the inner wall surface of the cavity and the slit. 9. The concentrating solar power generation system according to claim 8, wherein light is repeatedly reflected between reflectors on the back of the body to increase the amount of light provided for power generation in the solar power cell array.   The solar power cell array includes two or more types of solar power generation cells in which at least the wavelength band with high power generation efficiency is the first wavelength band and solar power generation cells in which the wavelength band with high power generation efficiency is the second wavelength band The concentrating solar power generation system according to any one of claims 1 to 9, wherein the cells are stacked.   The concentrating solar power generation system according to any one of claims 1 to 10, wherein the slit body includes a slit width adjusting mechanism that increases or decreases the slit width.   The slit body is composed of two plate-like members independent of each other, and the slit is formed between the opposing edges of the plate-like member, and the slit width adjusting mechanism slides the slit body to reduce the slit width. The concentrating solar power generation system according to claim 11, wherein the concentrating solar power generation system is increased or decreased.   The slit body is composed of two plate-like members independent of each other, the slit is formed between the opposing edges of the plate-like member, and the slit width adjusting mechanism is centered on a rotation shaft provided on the plate-like member. The concentrating solar power generation system according to claim 11, wherein the width of the slit is increased or decreased by rotating the plate member.   The concentrating solar power generation system according to claim 1, wherein the cylindrical lens is a Fresnel lens.   The concentrating solar power generation system according to any one of claims 1 to 14, wherein the cylindrical lens is provided with a photocatalytic coating so that the surface is not easily soiled.

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